Understanding DECsystem 5100 Self Test Failure

[Robert Jarratt]

> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Richard
> Loken
> Sent: 05 January 2015 16:19
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Understanding DECsystem 5100 Self Test Failure
> 
> On Sun, 4 Jan 2015, Robert Jarratt wrote:
> 
> > When I power up my DECsystem 5100 I get the output shown at the end of
> > this email. I thought this was to do with the DS1287 chip as it seems
> > be an NVRAM battery error (perhaps). Since I know these devices fail I
> > took out the DS1287, put in a socket and then bought a replacement
> > DS12887A. But I still get the same problem. It could be that I bought
> > a bad replacement, or that I
> 
> I hope you did not throw out the old one.  Assuming the new one is not
> compatible with you system or the battery in the new one is also dead, you
can
> find a set of instructions on the internet to drill a couple appropriate
holes in
> the DS1297 to disconnect the internal battery and attach an external
battery.


I have kept the original, but I am not sure that it was faulty in the first
place. I think the fault is something else, but I am not sure what. I did
find some pages on how to "repair" one, but I would rather be sure it is
faulty now before trying to do anything to it. For the record the RTC
self-test passes successfully.

Regards

Rob


> 
> I have the link some where if you cannot find it.
> 
> I have an Alphaserver 4100 (running VMS) within arm's reach that is turned
off
> because of a dead DS1287, I have the parts but I have not found the time
to do
> the repair.  This conversation reminds me that I have put that off for too
long.


I would consider at least taking out the old one and soldering in a socket
so that if necessary it is easy to replace.


Regards

Rob